HORIZON vs PARA: which needs more amplifier?

The Moondrop HORIZON is 32Ω at 94.1 dB/mW; the Moondrop PARA is 8Ω at 80.0 dB/mW. This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.

The PARA needs 14.1 dB more than the HORIZON to reach the same loudness — 100 mW against 3.9 mW.

The numbers that decide it

SpecificationHORIZONPARA
Impedance32 Ω8 Ω
Sensitivity94.1 dB/mW80.0 dB/mW
Sensitivity (voltage)109.0 dB/V101.0 dB/V
Power for 100 dB3.9 mW100 mW
Voltage for 100 dB0.35 V0.89 V
Current for 100 dB11.0 mA111.8 mA
Highest source impedance
that leaves them alone (one-eighth rule)
4.00 Ω1.00 Ω
Sources that reach 100 dB
out of 280
280130

Where the two part company

150 of the 280 sources have the power for the HORIZON but not for the PARA — Apple USB-C dongle (US), Apple USB-C dongle (EU), Generic CX31993 dongles, 147 more.

12 sources are low enough in output impedance for the HORIZON under the one-eighth rule but not for the PARA (FiiO KA13, FiiO K11, Schiit Vali 2+, 9 more).

130 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.

Both pages in full

Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: Moondrop HORIZON and Moondrop PARA. Every figure on this page comes from what Moondrop published, or is derived from it — what that maker publishes, counted.